Saltwater crocodile in Australia. Source: http://www.skitzone.com/wp-content/uploads/2010/03/australian-saltwater-crocodile01.jpg
Latin name: Crocodylus porosus: "Crocodylus", literally meaning "pebble worm" comes from the Greek word "krokodeilos". This was named because of its appearance. "Porosus" comes from the Latin word for "full of" and the Greek word of "porosis" meaning "full of callosities". This was used because of their snouts that have a lumpy surface on the top.
Description:
The saltwater crocodile is the largest reptile in the world. They are also called the estuarine crocodile.The average length for a female is 4 metres, and 5 metres for a male but it can grow up to 7 metres in length. These crocodiles are found in parts of eastern India, Southeast Asia and nothern Australia in rivers and swamps. They are grey and brown in colour with a strong body, a powerful tail, a huge head, heavy jaws and are known to be excellent swimmers. The saltwater crocodile feeds on fish, reptiles, birds and mammals while the youngs are limited to smaller animals such as amphibians. They lurk beneath the waters of rivers and swamps and when the perfect time has come, they would plunge out of the water without warning, pull their victim into the water and wait until the animal drowns before having their meal. The saltwater crocodile is also known to attack humans. They have a lifespan of up to 70-100 years.
Habitat:
Black parts are where saltwater crocodiles are found in the world. Source: http://upload.wikimedia.org/wikipedia/commons/9/92/Crocodylus_porosus_range.PNG
The habitats of the saltwater crocodile are in the warm climates of Sri Lanka and India, the Caroline Islands, Burma and Southeast Asia, Australia, Vanuatu and the Solomon Islands. They are sometimes found out in the sea, far away from land, because they can seim great distances for over a thousand kilometres.
The saltwater crocodile usually lives in coastal areas of swamps, rivers and billabongs. During the wet and dry seasons, these crocodiles move to different habitats due to their growth adaptations. For example, a young saltwater crocodile would live its first few years in freshwater rivers and as they get closer to being an adult, move into larger areas with more salinitity. This occurs because of the places when it comes to breeding.
Saltwater crocodiles on the muddy shores of Australia. Source: http://www.kimberleyaustralia.com/image-files/saltwater-crocodiles.jpg
In the wetland environment, the saltwater crocodile is the main predator of the food chain so they hunt for many different types of animals. But they are also seen as prey for other animals such as feral pigs, goannas, turtles, barramundi, sea eagles and other crocodiles. These crocodiles play an important role in the food chain of the wetland ecosystem because being both predator and prey, they keep the environment around them healthy.
Saltwater crocodiles are very territorial. Some crocodiles are even kicked out of their own habitats and into the sea. This causes the wide distribution of crocodiles living in the world ranging from South Asia to Northern Australia (Refer to map above).
Scientific Classification
Kingdom
Animalia
Phylum
Chordata
Class
Reptilia
Order
Crocodylia
Family
Crocodylidae
Subfamily
Crocodylinae
Genus
Crocodylus
Species
C. porosus
Labelled Diagram: Features of Saltwater Crocodile
Labelled Diagram of Saltwater Crocodile. Image from: http://www.darwinbluewater.com.au/images/site/the_beast/the_beast/saltwater_crocodile.jpg
Spikes on the top of the tail. Source: http://imagecache6.allposters.com/LRG/28/2885/VXHPD00Z.jpg
The tail of the saltwater crocodile is the size of 49.5% of its whole body length. The large size gives a lot of advantages for the reptile. It is used for helping the crocodile to swim through the water. The tail is broad so that it gives power when they move. There are spikes on the top of the tail that are used for thrusting at their prey and is also a vital device for temperature regulation. It is hard to catch food under the waters of swamps, so with the help of their tail, it makes it easier for saltwater crocodiles both when getting to their prey at fast speed and also for wacking at it.
Structural Adaptation 2: Huge Jaws
Closer view of the jaws. Source:http://ozmagic.homestead.com/files/crochccrocheadenlarge.jpg
Saltwater crocodiles have uneven and irregular sized teeth that are useful for grabbing and pulling their prey into the water. They are aggresive animals and in some cases, have been known to kill humans. Their heavy set of jaws contains 64-68 irregular teeth that can take on the pressure and force of a large animal. They can feast on wild pigs, buffaloes, kangaroos, horses and cattle. The jaws are constructed to be able to close quickly and tightly when catching prey. Their upper and lower jaws are designed to fit each other perfectly when they close with the fourth tooth of each side of the bottom jaw showing out because of its larger size. The reason for these huge, strong teeth is because of the size of the animals that saltwater crocodiles feast on.
Behavioural Adaptation 1: Frequent Change in Bod Temperature
Like all reptiles, the saltwater crocodile is cold blooded so their body temperature is the same as their surroundng air, land or water temperature. They normally live in the places where the air and water is warm all year round because of their lack of reptilian thermostat which keeps the reptile have a warm body temperature. Their body temperature is the same as their surroundings as they are cold blooded animals. The saltwater crocodile prefers to have a body temperature of about 30-33°C. They are often seen trying to maintain this body temperature by basking in the sun with their mouth wide open. Some zoologists claim that the reason for this is that while the body is being heated by the sun, the brain is cooled through evaporation from the palate. There are others saying that it has got something to do with strengthening the muscles in the jaw or showing off to other crocodiles.
Behavioural Adaptation 2: Communicating by Signals/Gestures
Signals/gestures are used between animals to communicate and that goes the same for saltwater crocodiles. A very common signal used among saltwater crocodiles is when a large one wants to tell the smaller ones "I give in". This is done by lifting their snout. Another signal used is making an inflated posture and arching their tail to create a kind of threatening look at other crocodiles. It also shows that they are in their own rights. When one wants to let others know that they are present in the area, they would make their body rigid and then swing their head around in power. Saltwater crocodiles are known as very territorial, meaning that they are very protective of their own territory/environment.
Physiological Adaptation: Exhaustion from Anaerobic Activity
Once a crocodile has been in exhausting activity for a short period of time such as capturing a prey or fighting with other crocodiles, they have used up a lot of energy and need time to rest before letting themselves be invovled in another strenuous activity. This is because they carry out these feirce acts without oxygen so they need a period of resting time in order to get back more oxygen. This non-oxygen activity is called anaerobic activity and is what causes the crocodiles to become exhausted afterwards. As a result of this activity, lactic acid builds up in the blood which is what is called acidic. This can lead to death even though the saltwater crocodile can withstand extreme levels of acidic blood more than most animals. This leads to the fact that big crocodiles larger than 5 metres in length can die of struggling in exhaustion from the anaerobic activity.
Crocodilian Species List. (2009). Crocodilian species - australian saltwater crocodile (crocodylus porosus). Retrieved July 9, 2010, from http://www.flmnh.ufl.edu/cnhc/csp_cpor.htm
Saltwater Crocodile (Crocodylus porosus)
Latin name:
Crocodylus porosus: "Crocodylus", literally meaning "pebble worm" comes from the Greek word "krokodeilos". This was named because of its appearance. "Porosus" comes from the Latin word for "full of" and the Greek word of "porosis" meaning "full of callosities". This was used because of their snouts that have a lumpy surface on the top.
Description:
The saltwater crocodile is the largest reptile in the world. They are also called the estuarine crocodile.The average length for a female is 4 metres, and 5 metres for a male but it can grow up to 7 metres in length. These crocodiles are found in parts of eastern India, Southeast Asia and nothern Australia in rivers and swamps. They are grey and brown in colour with a strong body, a powerful tail, a huge head, heavy jaws and are known to be excellent swimmers. The saltwater crocodile feeds on fish, reptiles, birds and mammals while the youngs are limited to smaller animals such as amphibians. They lurk beneath the waters of rivers and swamps and when the perfect time has come, they would plunge out of the water without warning, pull their victim into the water and wait until the animal drowns before having their meal. The saltwater crocodile is also known to attack humans. They have a lifespan of up to 70-100 years.
Habitat:
The habitats of the saltwater crocodile are in the warm climates of Sri Lanka and India, the Caroline Islands, Burma and Southeast Asia, Australia, Vanuatu and the Solomon Islands. They are sometimes found out in the sea, far away from land, because they can seim great distances for over a thousand kilometres.
The saltwater crocodile usually lives in coastal areas of swamps, rivers and billabongs. During the wet and dry seasons, these crocodiles move to different habitats due to their growth adaptations. For example, a young saltwater crocodile would live its first few years in freshwater rivers and as they get closer to being an adult, move into larger areas with more salinitity. This occurs because of the places when it comes to breeding.
In the wetland environment, the saltwater crocodile is the main predator of the food chain so they hunt for many different types of animals. But they are also seen as prey for other animals such as feral pigs, goannas, turtles, barramundi, sea eagles and other crocodiles. These crocodiles play an important role in the food chain of the wetland ecosystem because being both predator and prey, they keep the environment around them healthy.
Saltwater crocodiles are very territorial. Some crocodiles are even kicked out of their own habitats and into the sea. This causes the wide distribution of crocodiles living in the world ranging from South Asia to Northern Australia (Refer to map above).
Scientific Classification
Labelled Diagram: Features of Saltwater Crocodile
Adaptations:
Structural Adaptation 1: Powerful Tail
Structural Adaptation 2: Huge Jaws
Saltwater crocodiles have uneven and irregular sized teeth that are useful for grabbing and pulling their prey into the water. They are aggresive animals and in some cases, have been known to kill humans. Their heavy set of jaws contains 64-68 irregular teeth that can take on the pressure and force of a large animal. They can feast on wild pigs, buffaloes, kangaroos, horses and cattle. The jaws are constructed to be able to close quickly and tightly when catching prey. Their upper and lower jaws are designed to fit each other perfectly when they close with the fourth tooth of each side of the bottom jaw showing out because of its larger size. The reason for these huge, strong teeth is because of the size of the animals that saltwater crocodiles feast on.
Behavioural Adaptation 1: Frequent Change in Bod Temperature
Like all reptiles, the saltwater crocodile is cold blooded so their body temperature is the same as their surroundng air, land or water temperature. They normally live in the places where the air and water is warm all year round because of their lack of reptilian thermostat which keeps the reptile have a warm body temperature. Their body temperature is the same as their surroundings as they are cold blooded animals. The saltwater crocodile prefers to have a body temperature of about 30-33°C. They are often seen trying to maintain this body temperature by basking in the sun with their mouth wide open. Some zoologists claim that the reason for this is that while the body is being heated by the sun, the brain is cooled through evaporation from the palate. There are others saying that it has got something to do with strengthening the muscles in the jaw or showing off to other crocodiles.
Behavioural Adaptation 2: Communicating by Signals/Gestures
Signals/gestures are used between animals to communicate and that goes the same for saltwater crocodiles. A very common signal used among saltwater crocodiles is when a large one wants to tell the smaller ones "I give in". This is done by lifting their snout. Another signal used is making an inflated posture and arching their tail to create a kind of threatening look at other crocodiles. It also shows that they are in their own rights. When one wants to let others know that they are present in the area, they would make their body rigid and then swing their head around in power. Saltwater crocodiles are known as very territorial, meaning that they are very protective of their own territory/environment.
Physiological Adaptation: Exhaustion from Anaerobic Activity
Once a crocodile has been in exhausting activity for a short period of time such as capturing a prey or fighting with other crocodiles, they have used up a lot of energy and need time to rest before letting themselves be invovled in another strenuous activity. This is because they carry out these feirce acts without oxygen so they need a period of resting time in order to get back more oxygen. This non-oxygen activity is called anaerobic activity and is what causes the crocodiles to become exhausted afterwards. As a result of this activity, lactic acid builds up in the blood which is what is called acidic. This can lead to death even though the saltwater crocodile can withstand extreme levels of acidic blood more than most animals. This leads to the fact that big crocodiles larger than 5 metres in length can die of struggling in exhaustion from the anaerobic activity.
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